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The Basics

by
novalis
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Published on
Mar 25, 2005 04:55 PM

The basics about copyright and licensing

I get a lot of questions about licensing which seem easy to me. I've
just realized that the cause is probably that people don't understand
all the pieces of the Free Software licensing system. I say "system"
because the GPL really is like a piece of software that runs on top of
LegalOS XP (home edition). Even though there are many legal systems
in the world, most countries have agreed to the Berne Convention. So,
copyright laws are quite similar around the world.

So, here's a primer:

Copyright law grants to copyright holders some exclusive rights.

a. These rights include copying, modification (what copyright law
calls "preparing a derivative work"), and redistribution.

b. If you write software, you're probably the copyright holder, unless
you are at the time working for some company as an employee. You
don't have to do anything special to obtain a copyright. As soon as
you save the document, pixies sneak into your computer and deposit the
copyrights directly onto the document. But it's still a good idea to
use copyright notices.

Exclusive means that the copyright holder gets to decide who can
exercise these rights.

a. In order to let someone else exercise these rights, the copyright
holder issues a license.

If someone exercises the rights outside the terms of the license,
they're infringing the copyright.

a. We speak of these as "license violations".

b. Because the copyright holder is the only one whose legal rights
have been infringed, they're the only one who can enforce the license.

Sometimes, a copyright holder wants something very close to, but
not exactly, standard terms. In this case, they can issue an
exception to the license permitting this. That's effectively a
modification of the license which makes it strictly more permissive.

The copyright holder can do this because of (2) above.

There are at two common cases of this:

a. The standard terms don't permit linking to a library which
the copyright holder wants to permit linking to. FSF has written
exceptions for this case.

b. Someone has convinced the copyright holder that they should be
treated specially and have rights above the standard terms. Perhaps
this is because they have paid the copyright holder. Because the
terms for this can vary wildly, and can sometimes support proprietary
software, FSF doesn't have standard text for this.

You can also assign your copyright. By way of analogy, licensing
software to someone is like inviting them to visit your house;
assigning copyright to someone is like selling them your house.

a. You might want to assign your copyright to someone else if they
promise to do the work of enforcing the license, or they otherwise
won't take your patches.

We maintain a list of free software licenses. A license gets on
this list by consensus of our licensing committee. But the committee
isn't a bunch of alchemists. They don't even have pointy hats. They
just look at the terms of the licenses. Decisions are made based on
the Free
Software Definition.

Usually, you can tell if a license is a Free Software license by
matching its terms to other licenses in the license list. This is not
to say that a license which consists only of terms from other Free
licenses is ncessarily a free license. For example, if I took only
section 11 of the GPL and called it my license, it would (a) not be a
license and (b) not be free. But a license that differs from another
only in the name of sponsoring organization will be judged the same.

We encourage the use of standard licensing terms.

a. Writing a new license, rather than using an existing standard
license, is a bad idea because it increases the burden on people who
want to re-use your software. They have to understand some new set of
terms. And then they ask me to tell them if it's a free software
license.